Functional Groups

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Functional Groups of Organic Compounds
A functional group is a specific arrangement of atoms in the HC derivative other than carbon and hydrogen. Literally, the functional group determines the functions of the particular HC derivative in chemical reactions. This means that the specific properties of the HC derivative are due to its functional group. Each functional group is attached to an alkyl radical (R). An alkyl radical is one H atom less than the given alkane. The alkyl radical (R) uses the general formula CnH2n+1

Table of Common Functional Groups

Organic compounds that contain one or more hydroxyl groups . General formula for a class of organic compounds:
Consists of the functional group and the letter R which stands for the rest of the molecule General formula for alcohols : R–OH
Hydroxyl group, –OH,
Makes alcohols able to hydrogen-bond makes them soluble in water Uses of Alcohols:
Lotions, creams, and cosmetics usually contain an alcohol called glycerol to keep them moist Alternative fuels
Ex: gasohol, a one-to-nine ratio of ethanol and gasoline
Simple alcohols – Ethanol ; Poisonous to some extent

Methanol is used for the manufacture of plastics and synthetic fibers. When an –OH group is substituted for one hydrogen atom in ethane, the resulting alcohol is ethanol. Ethanol is a good solvent for many organic solutes that cannot dissolve in water. Alcoholic beverages contain ethanol.

Gasohol is a mixture of 10% ethanol and gasoline. It is used as a fuel or automobile that was developed in response to the energy crisis-way back 1970. Cereal grains like corn are fermented to produce ethanol. Alcohol Nomenclature

Name Parent hydrocarbon:
Longest chain containing hydroxyl group
Drop –e, add –ol
More than one hydroxyl group
2 -diol
3 -triol
Number so hydroxyl group has lowest number possible
Insert number immediately before name of parent hydrocarbon Common Names
 Chemical Formula |  IUPAC Name |  Common Name |
Monohydric alcohols |
CH3OH| Methanol | Wood alcohol|
C2H5OH| Ethanol | Grain alcohol|
C3H7OH| Isopropyl alcohol | Rubbing alcohol|
C5H11OH| Pentanol| Amyl alcohol |
C16H33OH| Hexadecan-1-ol| Cetyl alcohol |
Polyhydric alcohols |
C2H4(OH)2 | Ethane-1,2-diol| Ethylene glycol |
C3H5(OH)3 | Propane-1,2,3-triol| Glycerin |
C4H6(OH)4 | Butane-1,2,3,4-tetraol| Erythritol |
C5H7(OH)5 | Pentane-1,2,3,4,5-pentol| Xylitol |
C6H8(OH)6 | Hexane-1,2,3,4,5,6-hexol| Mannitol, Sorbitol | C7H9(OH)7 | Heptane-1,2,3,4,5,6,7-heptol| Volemitol |
Unsaturated aliphatic alcohols |
C3H5OH| Prop-2-ene-1-ol| Allyl alcohol |
C10H17OH| 3,7-Dimethylocta-2,6-dien-1-ol| Geraniol |
C3H3OH| Prop-2-in-1-ol| Propargyl alcohol |
Alicyclic alcohols |
C6H6(OH)6 | Cyclohexane-1,2,3,4,5,6-hexol| Inositol |
C10H19OH| 2 - (2-propyl)-5-methyl-cyclohexane-1-ol| Menthol | ESTHERS
Organic compounds in which two hydrocarbon groups are bonded to the same atom of oxygen General formula of an ether: R–O–R’
R’ represents a hydrocarbon group .R same or different hydrocarbon group . Not very reactive compounds. Relatively nonpolar
Some have pleasant odors, used in perfumes.
Ether molecules cannot form hydrogen bonds with each other, resulting in a relatively low boiling points compared to those of the analogous alcohols. The difference, however, in the boiling points of the ethers and their isometric alcohols becomes lower as the carbon chains become longer, as the van der Waals interactions of the extended carbon chain dominates over the presence of hydrogen bonding. Ethers are slightly polar. The C-O-C bond angle in the functional group is about 110°, and the C-O dipoles do not cancel out. Ethers are more polar than alkenes but not as polar as alcohols, esters, or amides of comparable structure. However, the presence of two lone pairs of electrons on the oxygen atoms makes hydrogen...
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